U.S. patent application number 14/564866 was filed with the patent office on 2015-06-18 for system and method for adjusting movement of an irrigation apparatus.
The applicant listed for this patent is AgSense, LLC. Invention is credited to Jesse L. Hohm, Michael D. Meyer, Terry D. Schiltz.
Application Number | 20150164007 14/564866 |
Document ID | / |
Family ID | 52112584 |
Filed Date | 2015-06-18 |
United States Patent
Application |
20150164007 |
Kind Code |
A1 |
Schiltz; Terry D. ; et
al. |
June 18, 2015 |
SYSTEM AND METHOD FOR ADJUSTING MOVEMENT OF AN IRRIGATION
APPARATUS
Abstract
A system and method for adjusting movement of an irrigation
apparatus to help compensate for transient conditions occurring
during operation of the apparatus to accomplish a substantially
uniform fluid application rate, and including transient conditions
such as a detected actual speed of movement of the span across the
field is lesser or greater than expected or such as a detected
actual flow rate of fluid to the irrigation system is lesser or
greater than expected.
Inventors: |
Schiltz; Terry D.; (Huron,
SD) ; Meyer; Michael D.; (Huron, SD) ; Hohm;
Jesse L.; (Huron, SD) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
AgSense, LLC |
Huron |
SD |
US |
|
|
Family ID: |
52112584 |
Appl. No.: |
14/564866 |
Filed: |
December 9, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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14104429 |
Dec 12, 2013 |
8924101 |
|
|
14564866 |
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Current U.S.
Class: |
700/284 |
Current CPC
Class: |
A01G 25/16 20130101;
A61M 2205/3351 20130101; G05B 15/02 20130101; A61B 17/00234
20130101; A61M 2205/12 20130101; A01G 25/092 20130101; A61B 1/00039
20130101; A61M 1/0058 20130101 |
International
Class: |
A01G 25/09 20060101
A01G025/09; G05B 15/02 20060101 G05B015/02; A01G 25/16 20060101
A01G025/16 |
Claims
1. A method of controlling movement of an irrigation system in a
field based upon at least one transient condition in the field, the
irrigation system including a span movable over the field, the span
being supported by a plurality of towers, at least one of the
towers having at least one wheel resting on the ground surface of
the field and being rotatable to advance the span across the field,
at least one of the towers having a motor assembly to rotate the
wheel of the tower, the method comprising: providing a remote
control unit on the irrigation system, the remote control unit
including a location determination assembly configured to determine
a location of the remote control unit on the span at a time;
receiving a selected fluid application rate by the remote control
unit; detecting an initial location of the remote control unit by
the location determination assembly; determining an expected
distance of movement of the remote control unit over at least one
time interval at an initial movement speed, moving the span for a
time interval in a manner corresponding to the selected fluid
application rate; at an end of the time interval, detecting a first
intermediate location of the remote control unit by the location
determination assembly; determining an actual distance of movement
during said time interval based upon the initial location and the
first intermediate location; comparing the actual distance of
movement to the expected distance of movement; determining if there
is a deviation between the actual distance of movement and the
expected distance of movement, and if a deviation exists, then
determining a magnitude of the deviation; and if there is a
deviation, then calculating an adjusted movement speed for a
subsequent time interval.
2. The method of claim 1 wherein, if no deviation exists between
the actual and expected distances of movement, then continuing to
move the span at the initial movement speed.
3. The method of claim 1 wherein the adjusted movement speed is
calculated to cause the remote control unit to be moved by the span
a corrective distance such that an actual distance of movement over
an immediate past time interval and the subsequent time interval is
substantially equal to a combination of the expected distances of
movement for the two time intervals.
4. The method of claim 1 additionally comprising generating an
adjusted control signal by the remote control unit corresponding to
the adjusted movement speed and providing the adjusted control
signal to the motor assembly to cause the motor assembly to operate
at a speed corresponding to the adjusted movement speed.
5. The method of claim 1 additionally comprising notifying the user
of the adjustment of the movement speed.
6. The method of claim 1 wherein providing the remote control unit
on the irrigation system includes positioning the remote unit on
the span at a location spaced from a center of rotation of the
span.
7. The method of claim 1 wherein providing the remote control unit
on the irrigation system includes interfacing the remote control
unit with a control wire of the irrigation system.
8. The method of claim 7 wherein interfacing the remote control
unit includes severing the control wire to create an upstream
portion of the control wire in communication with a main control
apparatus of the irrigation system and a downstream portion in
communication with the motor assembly, and connecting the upstream
portion of the control wire to an input of the remote control unit
and connecting the downstream portion of the control wire to an
output of the remote control unit.
9. The method of claim 8 additionally comprising outputting a
modified control signal from the remote control unit on the output
to the motor assembly, the modified control signal corresponding to
the adjusted movement speed.
10. The method of claim 1 wherein determining the expected distance
of movement includes calculating the expected distance of movement
using the selected application rate, the time interval, and a
distance of the remote control unit from a center of rotation of
the span.
11. The method of claim 1 wherein determining the expected distance
of movement includes calculating the expected distance of movement
for each time interval of a complete revolution of the span.
12. The method of claim 1 wherein moving the span includes
providing power to the motor assembly for at least a portion of the
time interval.
13. A method of controlling movement of an irrigation system in a
field based upon at least one transient condition in the field, the
irrigation system including a span movable over the field, the span
being supported by a plurality of towers, at least one of the
towers having at least one wheel resting on the ground surface of
the field and being rotatable to advance the span across the field,
at least one of the towers having a motor assembly to rotate the
wheel of the tower, the method comprising: providing a remote
control unit on the irrigation system, the remote control unit
including a location determination assembly configured to determine
a location of the remote control unit on the span at a time;
receiving a selected fluid application rate by the remote control
unit; establishing a baseline rate of fluid flow from the pump;
determining an initial movement speed based upon the baseline flow
rate of the pump and the selected fluid application rate; moving
the span for an initial time interval at the initial movement
speed; detecting a first actual flow rate of the pump during the
initial time period; comparing the first actual flow rate to the
baseline rate; determining if there is a flow deviation between the
first actual flow rate and the baseline rate; if the flow deviation
exists, then determining a magnitude of the flow deviation; and
calculating an adjusted movement speed for a subsequent time
interval, the adjusted movement speed being calculated to achieve
the selected application rate at the first actual flow rate.
14. The method of claim 13 additionally comprising moving the span
at an adjusted movement speed that is slower than the initial
movement speed when the first actual flow rate is less than the
baseline rate.
15. The method of claim 13 additionally comprising moving the span
at an adjusted movement speed that is faster than the initial
movement speed when the first actual flow rate is greater than the
baseline rate.
16. The method of claim 13 additionally comprising, if no flow
deviation exists between the first actual flow rate and the
baseline rate, continuing to move the span at the initial movement
speed.
17. The method of claim 13 additionally comprising, if the
magnitude of the flow deviation is not in a range of correctable
flow deviations, then setting the adjusted movement speed to a
minimum movement speed or a maximum movement speed over the
subsequent time interval.
18. A system for controlling movement of an irrigation system in a
field based upon at least one transient condition in the field, the
irrigation system including a span movable over the field, the span
being supported by a plurality of towers, at least one of the
towers having at least one wheel resting on the ground surface of
the field and being rotatable to advance the span across the field,
at least one of the towers having a motor assembly to rotate the
wheel of the tower, and a control wire for transmitting a control
signal to the motor assembly, the system comprising: a remote
control unit positionable on the span of the irrigation system, the
remote control unit having an input for interfacing to an upstream
portion of the control wire and an output for connecting to a
downstream portion of the control wire in communication with the
motor assembly, the remote control unit including: a location
determination assembly configured to determine a location of the
remote control unit on the span at a time; a processor; data
storage; wherein the processor is configured to execute a program
of instructions to: receive a selected fluid application rate via
the input of the remote control unit; detect an initial location of
the remote control unit using location data from the location
determination assembly; determine an expected distance of movement
of the remote control unit over at least one time interval at an
initial movement speed; transmit a control signal via the output of
the remote control unit to the motor assembly to cause the span to
move for a time interval in a manner corresponding to the selected
fluid application rate; at an end of the time interval, detect a
first intermediate location of the remote control unit using
location data from the location determination assembly; determine
an actual distance of movement during said time interval based upon
the initial location and the first intermediate location; compare
the actual distance of movement to the expected distance of
movement; determine if there is a deviation between the actual
distance of movement and the expected distance of movement, and if
a deviation exists, then determine a magnitude of the deviation; if
there is a deviation, then calculate an adjusted movement speed for
a subsequent time interval corresponding to the adjusted movement
speed, and transmit the adjusted control signal corresponding via
the output of the remote unit to the motor assembly.
Description
BACKGROUND
Field
[0001] The present disclosure relates to irrigation movement
systems and more particularly pertains to a new system and method
for adjusting movement of an irrigation apparatus to help
compensate for transient conditions occurring during operation of
the system.
SUMMARY
[0002] In one aspect, the present disclosure relates to a method of
controlling movement of an irrigation system in a field based upon
at least one transient condition in the field. The irrigation
system may include a span movable over the field, with the span
being supported by a plurality of towers and at least one of the
towers having at least one wheel resting on the ground surface of
the field and being rotatable to advance the span across the field,
and at least one of the towers has a motor assembly to rotate the
wheel of the tower. The method may comprise providing a remote
control unit on the irrigation system, with the remote control unit
including a location determination assembly configured to determine
a location of the remote control unit on the span at a time. The
method may further comprise receiving a selected fluid application
rate by the remote control unit, detecting an initial location of
the remote control unit by the location determination assembly,
determining an expected distance of movement of the remote control
unit over at least one time interval at an initial movement speed,
and moving the span for a time interval in a manner corresponding
to the selected fluid application rate. The method may also
comprise, at an end of the time interval, detecting a first
intermediate location of the remote control unit by the location
determination assembly, determining an actual distance of movement
during said time interval based upon the initial location and the
first intermediate location, comparing the actual distance of
movement to the expected distance of movement, determining if there
is a deviation between the actual distance of movement and the
expected distance of movement, and if a deviation exists, then
determining a magnitude of the deviation; and if there is a
deviation, then calculating an adjusted movement speed for a
subsequent time interval.
[0003] In another aspect, the disclosure relates to a method of
controlling movement of an irrigation system in a field based upon
at least one transient condition in the field. The irrigation
system may include a span movable over the field, the span being
supported by a plurality of towers, at least one of the towers
having at least one wheel resting on the ground surface of the
field and being rotatable to advance the span across the field, and
at least one of the towers having a motor assembly to rotate the
wheel of the tower. The method may comprise providing a remote
control unit on the irrigation system, with the remote control unit
including a location determination assembly configured to determine
a location of the remote control unit on the span at a time. The
method may further comprise receiving a selected fluid application
rate by the remote control unit, establishing a baseline rate of
fluid flow from the pump, determining an initial movement speed
based upon the baseline flow rate of the pump and the selected
fluid application rate, and moving the span for an initial time
interval at the initial movement speed, detecting a first actual
flow rate of the pump during the initial time period. The method
may also comprise comparing the first actual flow rate to the
baseline rate, determining if there is a flow deviation between the
first actual flow rate and the baseline rate, and if the flow
deviation exists, then determining a magnitude of the flow
deviation. The method may also include calculating an adjusted
movement speed for a subsequent time interval, with the adjusted
movement speed being calculated to achieve the selected application
rate at the first actual flow rate.
[0004] In still another aspect, the disclosure relates to a system
for controlling movement of an irrigation system in a field based
upon at least one transient condition in the field. The irrigation
system may include a span movable over the field, the span being
supported by a plurality of towers with at least one of the towers
having at least one wheel resting on the ground surface of the
field and being rotatable to advance the span across the field, at
least one of the towers having a motor assembly to rotate the wheel
of the tower, and a control wire for transmitting a control signal
to the motor assembly. The system may comprise a remote control
unit positionable on the span of the irrigation system, and having
an input for interfacing to an upstream portion of the control wire
and an output for connecting to a downstream portion of the control
wire in communication with the motor assembly. The remote control
unit may include a location determination assembly configured to
determine a location of the remote control unit on the span at a
time, a processor, and data storage. The processor may be
configured to execute a program of instructions to receive a
selected fluid application rate via the input of the remote control
unit, detect an initial location of the remote control unit using
location data from the location determination assembly, determine
an expected distance of movement of the remote control unit over at
least one time interval at an initial movement speed, and transmit
a control signal via the output of the remote control unit to the
motor assembly to cause the span to move for a time interval in a
manner corresponding to the selected fluid application rate. The
program of instruction may also be configured to, at an end of the
time interval, detect a first intermediate location of the remote
control unit using location data from the location determination
assembly, determine an actual distance of movement during said time
interval based upon the initial location and the first intermediate
location, compare the actual distance of movement to the expected
distance of movement, determine if there is a deviation between the
actual distance of movement and the expected distance of movement,
and if a deviation exists, then determine a magnitude of the
deviation. The program may also be configured to, if there is a
deviation, then calculate an adjusted movement speed for a
subsequent time interval corresponding to the adjusted movement
speed, and transmit the adjusted control signal corresponding via
the output of the remote unit to the motor assembly.
[0005] There has thus been outlined, rather broadly, some of the
more important elements of the disclosure in order that the
detailed description thereof that follows may be better understood,
and in order that the present contribution to the art may be better
appreciated. There are additional elements of the disclosure that
will be described hereinafter and which will form the subject
matter of the claims appended hereto.
[0006] In this respect, before explaining at least one embodiment
or implementation in greater detail, it is to be understood that
the scope of the disclosure is not limited in its application to
the details of construction and to the arrangements of the
components, and the particulars of the steps, set forth in the
following description or illustrated in the drawings. The
disclosure is capable of other embodiments and implementations and
is thus capable of being practiced and carried out in various ways.
Also, it is to be understood that the phraseology and terminology
employed herein are for the purpose of description and should not
be regarded as limiting.
[0007] As such, those skilled in the art will appreciate that the
conception, upon which this disclosure is based, may readily be
utilized as a basis for the designing of other structures, methods
and systems for carrying out the several purposes of the present
disclosure. It is important, therefore, that the claims be regarded
as including such equivalent constructions insofar as they do not
depart from the spirit and scope of the present disclosure.
[0008] The advantages of the various embodiments of the present
disclosure, along with the various features of novelty that
characterize the disclosure, are disclosed in the following
descriptive matter and accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The disclosure will be better understood and when
consideration is given to the drawings and the detailed description
which follows. Such description makes reference to the annexed
drawings wherein:
[0010] FIG. 1 is a schematic perspective view of elements of an
irrigation system according to the present disclosure.
[0011] FIG. 2A is a schematic block diagram of elements of one
illustrative embodiment of the system in which a remote control
unit is employed.
[0012] FIG. 2B is a schematic block diagram of elements of another
illustrative embodiment of the system in which a remote control
unit and a control panel unit are employed.
[0013] FIG. 3 is a schematic diagram of selected control elements
of the system according to an illustrative embodiment.
[0014] FIG. 4 is a schematic diagram of selected elements of the
system according to an illustrative embodiment, particularly
showing the path of fluid flow from the pump to the span.
[0015] FIG. 5A is a schematic diagram of a first portion of one
method of operation, according to an illustrative
implementation.
[0016] FIG. 5B is a schematic diagram of a second portion of the
method of operation of FIG. 3A, according to an illustrative
implementation.
[0017] FIG. 6A is a schematic diagram of a first portion of another
method of operation, according to an illustrative
implementation.
[0018] FIG. 6B is a schematic diagram of a second portion of the
method of operation of FIG. 4A, according to an illustrative
implementation.
[0019] FIG. 7 is a schematic diagram of operational aspects of the
system and method, according to an illustrative implementation.
[0020] FIG. 8 is a schematic diagram of operational aspects of the
system and method, according to an illustrative implementation.
DETAILED DESCRIPTION
[0021] With reference now to the drawings, and in particular to
FIGS. 1 through 8 thereof, a new system and method for adjusting
movement of an irrigation apparatus embodying the principles and
concepts of the disclosed subject matter will be described.
[0022] Typical irrigation systems, movement of the irrigator
structure is intended to proceed at a uniform rate that is not
intended to vary in order to provide a uniform fluid application
rate across the agricultural field. Applicants have recognized that
in the actual field environment, transient conditions may make this
ideal uniform movement difficult if not impossible, and that these
transient conditions may be virtually impossible to predict prior
to startup of system operation. Such transient conditions may
include, for example, variations in the actual movement progress of
the irrigation structure across the field which decrease (or
increase) the distance traveled across some portions of the field.
Thus, even though the structure is being driven at the same speed
throughout the field, conditions such as mud, obstructions,
variations in terrain, and the like may deviate the actual movement
distance from the ideal movement distance. These variations in
movement can affect the amount of fluid that is actually applied to
the field, as slower than expected movement applies more fluid to
the field than intended and faster than expected movement results
in a less than intended fluid application rate.
[0023] Another transient condition is the rate at which fluid,
usually water, is supplied to the irrigation system. Typically
water is supplied from a pump drawing from a well or a body of
water or even a water supply system, and the availability of water
will fluctuate as water is depleted from the ground aquifer or body
of water (and then replenished by rain) or as the water supply
system experiences variations in water demands. As the water flow
rate varies, so does the ability of the irrigation system to
deliver water to the field. The speed at which the irrigation
system moves across the field is typically based upon a single
uniform flow rate that may not be maintained throughout the day,
much less a growing season. Consequently, these variations in flow
from the fluid source can affect the amount of fluid that is
actually applied to the field, as lower than expected flow rates
may apply less fluid to the field than intended, and higher than
expected flow rates result in a fluid application rate that is
greater than intended.
[0024] Applicants have further recognized the need for a system
that is able to detect transient conditions that potentially affect
the fluid application rate, and are also able to adjust the
movement speed of the structure of the irrigation system to attempt
to minimize the effect of the condition upon the actual fluid
application rate and bring the application rate back to the
application rate selected by the user as much as possible.
[0025] In some aspects, the disclosure relates to a method of
controlling movement of an irrigation system in a field and
adjusting the operation based upon at least one transient condition
occurring in the field, in order to accomplish a substantially
uniform fluid application rate of the fluid onto the surface of the
field. In other aspects, the disclosure relates to a system and
apparatus that carries out, or at least contributes to, the
execution of elements of the method. Detection of conditions may
occur at various time intervals, and may typically occur at regular
and substantially uniform time intervals, although varying time
intervals may be utilized. The length of the time intervals
utilized may include any suitable time interval. In some
implementations, the time interval may be greater than one minute,
and in some implementations the time interval may be less than
approximately 30 minutes. In some implementations, the time
interval may be between approximately 1 minute and approximately 30
minutes, and may be between approximately 1 minute and
approximately 15 minutes.
[0026] For the purposes of this disclosure, transient conditions
are conditions of a type that may arise during a cycle of operation
the operation of the system in the field and that are relatively
unpredictable as to the duration and the magnitude of deviation
from an expected or base line state for the particular condition.
For example, the transient condition may include a detected actual
distance of movement of structure of the irrigation system in the
field that deviates from an expected movement distance. As another
example, the transient condition may include a detected actual flow
rate of fluid to the irrigation system that deviates from a
baseline flow rate. Other transient conditions may include
detectable conditions that may affect the actual fluid application
rate, and the effect on the fluid application rate may be
ameliorated or lessened through the adjustment of the movement
speed of the structure of the irrigation system. The system and
method disclosed may help to compensate for the effect of one or
more transient conditions on the fluid application rate.
[0027] In one aspect, the disclosure relates to an irrigation
system 10 that includes a span 12 which carries a fluid such as
water from an inboard end 14 to an outboard end 16 to dispense
fluid to locations along the span onto distributed areas of the
field surface. Although aspects of the disclosure may be
implemented on irrigation systems of various configurations and
geometries, one of the most preferred applications is on a center
pivot irrigation system configuration, and will be described in
that environment with the understanding that aspects may be easily
adapted to other irrigation system arrangements. The span 12 may
extend outwardly from a center of rotation located generally at the
inboard end 14, and thus may rotate about the center. Typically,
the span 12 includes a plurality of span segments 20 that are
connected together in a substantially linear arrangement, but often
with some flexibility in the connection such that deviation from a
completely linear arrangement is possible. The span segments 20 may
be formed by pipe that carries the fluid along the span, and that
are suitable connected in fluid communication at the junctures of
the span segments. The plurality of span segments 20 may include an
end span segment 22 with the outboard end 16 at the end of the end
span segment.
[0028] The span 12 may be supported above the field surface by one
or more towers 24, and typically a plurality of towers are employed
with a tower being located adjacent to each (although not
necessarily every) juncture between span segments. An end tower 26
may be the tower positioned relatively closest to the outboard end
14 of the span. At least one of the towers 24 has a wheel 28
resting on the ground surface of the field and which is rotatable
by a motor assembly 30 to advance the span across the field.
Commonly, each tower will have a pair of the wheels 28, and each
tower will have a motor assembly. The motor assembly 30 may
comprise a motor 32 and a power control 34 for controlling the
supply of power to the motor, and thereby the operation (or in
operation) of the motor and the wheels connected to the motor. In
some embodiment, the power control 34 may include a relay.
[0029] The irrigation system 10 may also include a control wire 36
from a main control apparatus 38 of the irrigation system to the
power control 34. In many embodiments, the main control apparatus
38 may be set to a selected fluid application rate by a user, such
as a farmer in the field, and in some popular implementations the
fluid application rate is set as a percentage of the maximum
application rate achievable by the irrigation system. The maximum
application rate is usually achieved at the slowest movement speed
for the span, and the conversely the minimum application rate is
achieved at the fastest movement speed. Conventionally, the
drivetrain (e.g., motor and wheels) of a span on the system is only
able to turn at one speed, so to change the speed of movement of
the span requires a series of "on" and "off" cycles for the motor
assembly to turn the wheels, and in this sense (and for the
purposes of this description), the term "movement speed" relates to
the total time that would be required for the span to make one
revolution, and not the actual velocity of the span. Thus, the
greater the amount of time that the motor assembly is in an "on"
cycle as compared to the time that it is in an "off" cycle, the
relatively faster the movement speed of the span. Conventionally,
the on and off cycle times are controlled by the main control
apparatus 38 (according to the set selected application rate) via a
control signal transmitted along the control wire 36 by the control
apparatus 38. The control signal generally corresponds to the
selected fluid application rate, and may be represented on the
control wire by a period that includes a sub-period of power on and
a sub-period of power off. For example, if a complete cycle
includes 60 seconds, the sub-period of power on may be 40 seconds,
and the sub-period of power off may be 20 seconds, providing an
approximately 66% duty cycle. Increasing the number of seconds in
the on cycle and decreasing the number of seconds in the off cycle
will increase the movement speed of the span. In many irrigation
system installations, the control signal is used to control the
movement of the endmost tower (adjacent to the en span segment) and
the remainder of the towers move in a "follow the leader" manner
that is conventional and well known to those skilled in the
art.
[0030] The irrigation system 10 may also include a fluid supply
which is often (although not necessarily) a ground well, a body of
water or a watercourse. A pump 40 is often used to move the fluid
from the fluid supply to the span, and a flow rate detector 42 may
be associated with the pump or a pipe leading to the span to detect
the actual flow rate of the fluid to the span as the availability
of water from these sources may not be consistent. The flow rate
detector 42 may generate a flow rate signal that corresponds to the
actual flow rate being detected by the detector at any given
time.
[0031] Another aspect of the disclosure relates to a remote control
unit 44 suitable to be used with an irrigation system, such as a
system 10 with elements disclosed herein (see FIGS. 2A and 2B).
FIG. 2A shows one implementation in which a remote control unit may
be employed without direct interface with the main control
apparatus 38 of the span, such as for functions such as speed
control and end spray gun control, but optionally may be interfaced
through a control panel interface to control functions such as
movement direction, and start/stop operations. FIG. 2B shows
another implementation in which a remote control unit 44 is
utilized with a control panel unit 45 which may be interfaced with
the main control apparatus of the system. In the implementation
shown in FIG. 2B, the remote control unit and control panel unit
may communicate in any suitable manner, such as by wire or
wirelessly, such as by radio frequency signals using any suitable
communication frequencies and protocols, including but not limited
to Wi-Fi, Wi-MAX, Bluetooth, and the like. In embodiments employing
both units 44, 45, many of the various functions described in this
disclosure (even if described as being performed by one or the
other of the units) may suitably be performed by either of the
units.
[0032] The remote control unit 44 is a device that may be
controlled remotely through a communication channel that is most
preferably wireless, but optionally could be conducted through a
wire. Further, communication with the remote control unit 44 may be
bidirectional through a transceiver, although the ability to
receive signals is most important to suitable operation. The
control unit is remote in the sense that it may be controlled from
a location that is remote from the device, typically miles if not
hundreds of miles away, although the distance is not critical. The
control of the unit 44 may be exercised through a communication
network, such as a communication network utilizing cellular
transmission and receiving devices and frequencies, although
wireless communication networks utilizing other technologies and
frequencies may also be utilized. The elements that exercise
control of the remote control unit 44 may utilize aspects of the
technology disclosed in U.S. Pat. No. 7,953,550 issued May 31,
2011, which is hereby incorporated by reference in its
entirety.
[0033] The remote control unit 44 may be configured as a device
that may be carried on the span and may be housed in a case that is
capable of resisting the elements and exposure encountered in an
agricultural field. The remote control unit 44 may have an input 46
and an output 48, with the input 46 being connectable to the
control wire 36 to receive the control signal and the output being
connectable to the power control 34 of the motor assembly 30. The
remote control unit may be configured and programmed to receive the
control signal on the control wire through the input 46, and
determine the selected fluid application rate selected by the user
by, for example, sampling the signal over a full period and
determining the relative length of the on period and the off
period. The remote control unit may generate and transmit through
the output 48 a modified control signal to the motor assembly 30 to
provide operation of the motor assembly that may be different from
the operation that would be effected if the control wire with the
control signal were supplied directly to the motor assembly without
the intervention of the remote control unit. Under some conditions,
the control signal at the output 48 may not be modified from the
signal at the input 46.
[0034] The remote control unit 44 may also include a location
determination assembly 50 that is configured to determine a
location of the remote control unit at a particular time, or at
time intervals. The location determination assembly 50 may provide
the location in terms of a set of location coordinates, such as
longitude and latitude. In some of the most preferred embodiments,
the location determination assembly 50 includes a Global
Positioning Satellite (GPS) signal receiver for receiving GPS
satellite signals (as well as other positioning signals) that
indicate the coordinates of the location of the unit 44, as well as
the tower or other portion of the span on which the unit 44 may be
mounted or carried.
[0035] The remote control unit 44 may further include a
communication means suitable for communicating over longer
distances for the purpose of communicating with entities at a
greater distance. For example, the entity may be accessible through
a wireless communication network and the entity may reside on a
data or computer communication network, although use of wired
communication channels such as the Plain Old Telephone System
(POTS) system may be used to less advantage. In one of the
preferred implementations of the invention, a cellular telephone
system is utilized as a wireless means of communication and a
cellular transceiver 52 is employed in the remote control unit 44
to provide communication ability to a cellular antenna or tower 54
in the region of the center pivot irrigation system. The entity may
thus be a web server 56 that is able to communicate with the
cellular telephone (or POTS) communication network as well as a
data communication network 58 (e.g., the Internet). Other means for
communicating may be employed, but as access points to cellular
networks (i.e., antenna towers) become more ubiquitous, even in
rural areas, the cellular transceiver 52 is able to provide
wireless communication to the cellular network 58 (and thus provide
access to the POTS network) without having to run a hard wired
connection to the field, which can be prohibitively expensive. It
will be recognized by those skilled in the art that the type or
types of networks may be varied without departing from the spirit
of the disclosure. The cellular transceiver 52 of the remote
control unit is thus able to communicate with the web server 56
through the cellular network 58 by a data transmission channel
through the network. Optionally, the cellular transceiver may dial
up the server through voice communication channel. The web server
56 is thereby able to receive location and status information from
the remote control unit 44, while the server is able to provide
operational instructions and programs of instructions to the remote
control unit and other units. The web server 56 is in turn
accessible by the user's communication device 60 (which may
comprise a computer, a personal digital assistant, a smartphone, or
virtually any device with the ability to at least receive and
display information) through a data communication network (e.g.,
Internet) or other communication network. The user is thus able to
communicate instructions, or programs of instructions, to the
remote control unit 44. The remote control unit and/or the control
panel unit may also include a processor for providing information
and communication processing functions, as well as storage for
storing, for example, data and instructions for moving and
operating various aspects of the system 10.
[0036] The flow rate detector 42 may be provided with a suitable
means of communicating the flow rate signal to at least one of the
units 44, 45 and/or the web server. The communication may be
carried using wired or wireless means such as radio frequency
transmissions using any suitable communication frequencies and
protocols, including but not limited to Wi-Fi, Wi-MAX, Bluetooth,
and the like. Optionally, the flow rate detector may communicate
with the web server in any suitable manner, such as cellular
network communication.
[0037] Another aspect of the disclosure relates to the method of
controlling movement of an irrigation system, such as a system
having some or all of the elements and attributes described above
with respect to system 10, in a manner that compensates or adjusts
for transient conditions such as the actual movement progress of
the span over the surface of the field. The method may include
providing an irrigation system with one or more elements described
in this disclosure.
[0038] The method may include providing a control with some or all
aspects described herein for the remote control unit 44, and may
also include providing the span 12 with the remote control unit 44.
The step of providing may involve positioning the remote unit 44 on
the span, such as at a position toward the outboard end 16 of the
span and may be on the end span segment 22. In some
implementations, the unit 44 may be positioned adjacent to the end
tower which is highly beneficial to increase the accuracy for
determining location and also is convenient for controlling the end
tower. Providing the remote control unit 44 on the span may further
include interfacing the unit 44 with the controls of the irrigation
system, and may include severing the control wire 36 to create an
upstream portion 36A of the control wire in communication with the
main control apparatus 38 and a downstream portion 36B in
communication with the power control 34 of the motor assembly 30.
The interfacing step may also include connecting the upstream
portion 36A of the control wire to the input 46 of the control unit
44, and connecting the downstream portion 36B of the control wire
to the output 48 of the unit 44.
[0039] The method may also comprise the step of receiving the
selected fluid application rate by the remote control unit 44,
which may include receiving the control signal by the input 46 of
the control unit 44 through the upstream portion 36A of the control
wire. In some implementations, the receiving step may include
monitoring and decoding the control signal to determine, for
example, a ratio of the time for the sub-period of power on to the
time for the sub-period of power off. This information regarding
the user selected fluid application rate may form the basis for
setting the initial movement speed for the span, which would be the
continuous movement speed throughout the rotation of the span if
the conditions in the field were not subject to transient
conditions that may call for changes in the movement speed as the
span is making a complete rotation cycle. In embodiments utilizing
a control panel unit 45, the selected fluid application rate may be
received by the panel unit 45.
[0040] Another step of the method may be to calculate an expected
distance of movement of the remote control unit 44 over at least
one time interval at the base or initial movement speed, and the
distance of movement of the unit 44 will generally correspond to
the distance moved by the end tower 26 if the unit is positioned
adjacent to, or on, the end tower. The expected distance of
movement by the unit 44 may be affected by, and thus may be based
upon, the selected application rate (which provides the initial
movement speed), a time interval between location determinations,
and the distance of the remote control unit from the center of
rotation of the span. The expected movement distance for each time
interval will typically be substantially equal, and the step may
include calculating an expected location for the control unit 44
after each of the time intervals of a complete revolution of the
span, although this is not necessary. The base movement speed may
represent a movement speed for ideal conditions, such as level and
dry ground conditions in which wheel slippage is not a significant
factor in the actual movement distance achieved.
[0041] The method may also include detecting an initial location of
the remote control unit 44 by the location determination assembly
50 of the unit 44, and may include determining the location
coordinates of the unit 44 via the GPS receiver. The initial
location may be stored in memory for later use in determining the
distance moved by the control unit over one or more time
intervals.
[0042] A further aspect of the method may include moving the span
12 for the time interval in a manner corresponding to the selected
fluid application rate which typically the initial movement speed.
As previously stated, the span may not be moving throughout the
entire time interval, as the movement of the span usually involves
a sub-period of movement and a sub-period of non-movement when the
span is stopped. The step may include providing power to the motor
assembly for at least a portion of the time interval, such as the
sub-period of power on. The control signal provided to the motor
assembly may be modified, but in some situations or conditions, the
control signal may not be modified, such as when the unmodified
control signal would provide the suitable movement speed.
[0043] Approximately at the end of the time interval, the method
contemplates detecting a first intermediate location of the remote
control unit 44 via operation of the location determination
assembly 50. Using the first intermediate location information, the
method may include determining an actual distance of movement
during time interval based upon the distance between the initial
location and the first intermediate location. Then, using the
actual distance of movement, the method may also include comparing
the actual distance of movement to the expected distance of
movement. It may be determined if there is a deviation of
difference between the actual distance of movement and the expected
distance of movement, and if a deviation in the distances exists, a
magnitude of the deviation.
[0044] If no deviation exists between the actual and expected
distances of movement, then the method may include continuing to
move the span at the initial (or optionally the most recently-used)
movement speed for the next time interval so that the movement
distance after that subsequent interval may be checked against the
expected movement distance over the interval. If a deviation in
movement distances is detected, then the method may optionally
contemplate determining if the magnitude of the deviation exceeds a
permitted level of deviation, which may be a degree of deviation
below which the difference is so minimal or inconsequential that it
can be ignored. If the magnitude of the deviation does not exceed
the permitted level of deviation, then the initial (or most recent)
movement speed may be maintained through the subsequent time
interval until the actual and expected distances are compared
again.
[0045] In cases where the magnitude of the deviation is large
enough that it needs to be addressed, such as if it exceeds the
permitted level of deviation, then the method may include
determining if the deviation of the actual distance of movement is
greater or lesser than the expected distance of movement. In other
words, determining if the movement of the span caused the control
unit 44 to fall short of the expected location (e.g., undershoot),
or exceed the expected location (e.g., overshoot).
[0046] As a further option, the method may include a step of
determining if the magnitude of the deviation is in a range of
correctable deviations, or deviations that are of too great of a
magnitude for it to be practical or feasible to attempt to correct
the deviation. The range of correctable deviations may vary
depending upon various factors, and the capability to correct may
depend, for example, upon the relative length of the time interval
over which the deviation may be attempted to be corrected as longer
time intervals provide a greater time period over which to make an
adjustment of the movement speed. Optionally, there may not be any
deviation that is too large for the system to attempt to correct,
although this approach may not be practical. If it is determined
that the magnitude of the deviation is not in the range of
correctable deviations, then the system may provide a notice to the
user's computer or electronic device via the communication network
of the inability to attempt to correct the deviation. In some
implementations, an adjusted movement speed may be set for the
subsequent time interval that is a predefined maximum speed if the
deviation is negative (e.g., the actual distance moved by the span
is less than the expected distance) or that is a predefined minimum
speed if the deviation is positive (e.g., the actual distance moved
by the span is greater than the expected distance).
[0047] In the case where the magnitude of the deviation is in the
range of correctable deviations, then a step of calculating an
adjusted movement speed for the subsequent time interval may be
performed. The adjusted movement speed may be calculated to cause
the span 12 to move the remote control unit 44 for a corrective
distance such that an actual distance of movement over the
immediate past time interval and the subsequent time interval is
substantially equal to a combination of the expected distances of
movement for the two time intervals.
[0048] When a corrective distance is determined, an adjusted
control signal may be generated, such as by the remote control
unit, that corresponds to the adjusted movement speed. The adjusted
control signal may be provided or transmitted to the motor assembly
through the downstream control wire 36B to cause the motor assembly
30 to operate at a speed that corresponds to the adjusted movement
speed. In some embodiments, the user may be notified of the
adjustment of the movement speed, such as by a transmission through
the communication network to the user's communication device.
[0049] Steps of the process may be repeated for each time interval
until system operation is ceased. In some implementations, once the
actual movement distance substantially corresponds to the expected
movement distance at a time interval, the movement speed for the
subsequent time interval may be the initial movement speed, or in
some implementations may be the adjusted movement speed of the most
recent time interval.
[0050] An illustrative operational example is shown in FIG. 7,
which schematically illustrates a relationship between the expected
movement distances, actual movement distances, and movement speeds.
As shown in the upper line of FIG. 7, the expected movement
distances are calculated and expected to be substantially uniform
from one time interval to the next in order to achieve a complete
movement (e.g., rotation) of the span in a given overall time
period to achieve the selected fluid application rate. The span is
expected to move from position A to position B in the first time
interval, from position B to position C in the second time
interval, and so on. As shown in the second line of FIG. 7, in
which the actual distance of movement are illustrated, after the
first time interval the actual movement distance is less than the
expected movement distance, and actual position B is short of the
expected position B. As illustrated in the third line of FIG. 7,
the movement speed of the span is increased in the second time
interval as compared to the first time interval (e.g., from an
initial movement speed to a faster movement speed) to attempt to
compensate for the shortfall in the actual movement distance during
the first time interval. As shown in the first and second lines of
FIG. 7, after the second time interval the deficit has been made up
and the actual position C substantially corresponds to the expected
position C as the actual movement distance over the second time
interval has exceeded the expected movement distance to a
sufficient degree to make up for the prior deficit. Since the
expected and actual positions C correspond, the movement speed for
the third time interval may be returned to the initial movement
speed.
[0051] Further illustrated in FIG. 7 is that during the third time
interval, the actual movement distance exceeds the expected
movement distance, so that actual position D is further along the
path of movement than expected position D. Consequently, the
movement speed in the fourth time interval is decreased relative to
the initial movement speed to a degree that is calculated to make
the actual position E at the end of the fourth time interval
correspond to the expected position E. After the fourth time
interval, the surplus travel distance after the third time interval
has been compensated for, and the actual position E substantially
corresponds to the expected position E. The movement speed of the
span may be decreased to the initial movement speed for the fifth
time interval.
[0052] A further aspect of the disclosure relates to the method of
controlling movement of an irrigation system in a manner that
compensates or adjusts for a transient conditions such as the
actual flow rate of fluid to the span as compared to, for example,
the expected or usual or baseline flow rate provided to the span.
The method may include providing an irrigation system with one or
more elements described in this disclosure, and may further include
establishing a baseline rate of fluid flow from the pump for use in
comparing to the actual flow rate observed at time intervals as the
system operates. The establishment of the baseline rate may include
detecting and recording a normal flow rate from the pump under
typical conditions, or even calculating an average flow rate from
various times and various conditions.
[0053] The method may further include receiving the selected fluid
application rate, such as by the remote control unit 44 or the
control panel unit 45, as indicated through the action of the user
at the main control apparatus or by other means. In some
implementations, the remote control unit may determine a base or
initial movement speed of the span based upon the baseline flow
rate of the pump and the selected fluid application rate. The
initial movement speed may form a normal or base movement speed
used when the actual flow rate is substantially equal to the
baseline flow rate. The span may be moved for the time interval in
a manner that generally corresponds to the selected fluid
application rate, which may include causing power to be provided to
the motor assembly for at least a portion of the time interval
through the control signal on the downstream portion of the control
wire. The control signal may be modified or may be unmodified as
compared to the control signal supplied to the remote control
unit.
[0054] The method may further include detecting a first actual flow
rate of the pump for the time interval, such as by receiving the
flow rate signal from the flow rate detector 42. The flow rate
measurement may be a single instantaneous or momentary measurement
of the flow rate at some point during the time interval, or may be
a composite or average of multiple flow measurements over the
relevant time interval. The remote control unit may receive the
actual flow rate measurement, and may compare the first actual flow
rate to the baseline rate and determine if there is a flow
deviation as the first actual flow rate deviates from the baseline
rate. If a flow deviation exists, then a magnitude of the flow
deviation may be determined.
[0055] If it is determined that no significant flow deviation
exists between the first actual flow rate and the baseline rate,
then the span may be caused to continue to move at the initial or
base movement speed. If it is determined that there is a flow
deviation between the actual and baseline flow rates, then it may
further be determined if the magnitude of the flow deviation
exceeds a permitted or acceptable level of flow deviation. If the
magnitude of the flow deviation is within the permitted level of
flow deviation, then the span may be continued to be moved at the
base movement speed.
[0056] If the magnitude of the flow deviation exceeds the permitted
level of flow deviation, then a determination if the flow deviation
of the flow rate is greater or lesser than the baseline flow rate
may be made. The method may further include making a determination
if the magnitude of the flow deviation is in a range of correctable
flow deviations, or flow deviations that may be compensated for
through the alteration or adjustment of the movement speed of the
span. If the magnitude of the flow deviation is determined to not
be in the range of correctable flow deviations, then a notice may
be provided to the user that indicates the inability to
sufficiently adjust the speed to adequately or effectively
compensate for the flow deviation. In such an instance, an adjusted
movement speed may be set for the subsequent time interval that is
a predefined maximum speed if the deviation is negative (e.g., the
actual flow rate is less than the baseline flow rate) or that is a
predefined minimum speed if the deviation is positive (e.g., the
actual flow rate is greater than the baseline flow rate).
[0057] If the magnitude of the flow deviation is in the range of
correctable deviations, then the method may include the step of
calculating an adjusted movement speed for the subsequent time
interval, with the adjusted movement speed being calculated to
achieve the selected application rate at the first actual flow
rate. In some implementations, a first actual flow rate in which
the flow deviation is below the baseline rate results in an
adjusted movement speed that is slower than the base movement
speed, and a first actual flow rate in which the deviation is above
the baseline rate results in an adjusted movement speed that is
faster than the base movement speed.
[0058] When a corrective adjusted movement speed is determined, an
adjusted control signal may be generated that corresponds to the
adjusted movement speed. The adjusted control signal may be
provided or transmitted to the motor assembly through the
downstream control wire 36B to cause the motor assembly 30 to
operate at a speed that corresponds to the adjusted movement speed.
In some embodiments, the user may be notified of the adjustment of
the movement speed, such as by a transmission through the
communication network to the user's communication device.
[0059] Steps of the process may be repeated for each time interval
until system operation is ceased. In some implementations, when the
actual flow rate substantially corresponds to the baseline flow
rate at a time interval, the movement speed for the subsequent time
interval may be the base movement speed, or in some implementations
may be the adjusted movement speed of the most recent time
interval.
[0060] An illustrative operational example is shown in FIG. 8,
which schematically illustrates a relationship between the baseline
flow rate, actual flow rates, and movement speeds. As shown in the
upper line of FIG. 8, the baseline flow rate is calculated and
expected to be substantially uniform from one time interval to the
next in order to achieve a substantially uniform fluid application
rate to achieve the selected fluid application rate. In the
illustration, during the first time interval, the actual flow rate
is detected to be less than the baseline flow rate (the baseline
flow rate is indicated by a broken line), and during the second
(subsequent) time interval the movement speed is adjusted and
decreased to a degree that is calculated to apply fluid on the
field at the selected application rate at the reduced flow rate
detected. During the second time interval, it is detected that the
actual flow rate approximately corresponds to the baseline flow
rate, and so the movement speed is returned to the base movement
speed over the third interval. During the third time interval, it
is determined that the actual flow rate is greater than the
baseline flow rate, so during the fourth (subsequent) time
interval, the movement speed is adjusted to be faster than the base
movement speed. As the actual flow rate is approximately equal to
the baseline flow rate in the fourth time interval, then the
movement speed is adjusted back to the base movement speed during
the fifth time interval.
[0061] It should be recognized that the system and method of the
disclosure may detect and compensate for two or more transient
conditions during the same period of operation, and may make
multiple adjustments to the movement speed for a time interval,
some of which may decrease or even cancel out each other. In some
implementations, compensation based upon one of the conditions may
be given priority over compensation for another condition. For
example, in a system which detects variations in both actual
movement and flow rate, the calculated compensation for decreased
flow rate may take priority over any compensation for an actual
movement distance that falls short of the expected distance. In
other implementations, amelioration of all conditions may be given
equal priority.
[0062] It should be appreciated that in the foregoing description
and appended claims, that the terms "substantially" and
"approximately," when used to modify another term, mean "for the
most part" or "being largely but not wholly or completely that
which is specified" by the modified term.
[0063] It should also be appreciated from the foregoing description
that, except when mutually exclusive, the features of the various
embodiments described herein may be combined with features of other
embodiments as desired while remaining within the intended scope of
the disclosure.
[0064] Further, those skilled in the art will appreciate that the
steps shown in the drawing figures may be altered in a variety of
ways. For example, the order of the steps may be rearranged,
substeps may be performed in parallel, shown steps may be omitted,
or other steps may be included, etc.
[0065] With respect to the above description then, it is to be
realized that the optimum dimensional relationships for the parts
of the disclosed embodiments and implementations, to include
variations in size, materials, shape, form, function and manner of
operation, assembly and use, are deemed readily apparent and
obvious to one skilled in the art in light of the foregoing
disclosure, and all equivalent relationships to those illustrated
in the drawings and described in the specification are intended to
be encompassed by the present disclosure.
[0066] Therefore, the foregoing is considered as illustrative only
of the principles of the disclosure. Further, since numerous
modifications and changes will readily occur to those skilled in
the art, it is not desired to limit the disclosed subject matter to
the exact construction and operation shown and described, and
accordingly, all suitable modifications and equivalents may be
resorted to that fall within the scope of the claims.
* * * * *